Tempest troubleshooting

Hi guys,

My Tempest just developed a problem that I've never come across before,
so I was hoping that somone here might have some more insight into it.

In attract mode, the "Game Over" text now appears 4 times larger than
normal, and it shows up in the wrong location on screen. It flits
between where it's supposed to be up top, and the middle of the screen.
Some of the other text, is doing this to, but I forget which phrases
they are. The high score table is not affected.

If I coin up the game, the game plays and displays perfectly.

Self test reveals no errors or problems.

As soon as the game goes back into attract mode, I get this crazy text
problem. When the machine is in self test, I also have the text problem
with the game difficulty setting and number of ships per game.

Because the game works correctly in game mode, it seems that I can rule
out the possibility of a faulty analog output stage. Seems more like a
digital problem. As I said, everthing checks out in self test, so if
you can believe that information, then the mathbox is OK, and the game
code is good, and the rams are good. Aiyee.. still seems like a ram
problem to me, but I'd like to believe the self test knows what it's
doing!!

Anyone have some ideas of what I might be looking for?

Thanks for any input. I'll have to check Nick's Tempest troubleshooting
page next, but I don't remember reading anything about this type of
problem there, but it's been a while.

Joel-
Received on Tue Dec 9 13:16:32 1997